I've got a 68000 POD that I stored away when I converted my garage back in 2003 (not the house, the one before) and when I got it back out again it no longer worked. No smoke, no bangs, nothing like that.

Can anyone help me to get this working as I'm starting to build up quite a collection of non working 68000 boards and it seems to me that they all share pretty much the same problem. When they don't work you get a white screen and not a lot else to go on!!

I would have to find the POD to report on exactly what it does or doesn't do (I think it's on a shelf in my office) but I seem to remember it simply fails self test and doesn't work

One of the problems is, realistically I think you need a second 68K pod to fix it and obviously I only have the one.

Cheers dude - I'll dig it out later. I'm not 100% sure I'm keen on borrowing something as valuable in case it goes wrong in my hands (which has a nasty habit of happening to me!)

I'll get a ROM check on it later. That's actually a good point. I probably also need to see if I can find something with a working 68K so that I can confirm the processor. Assuming it has one in it. Pretty sure it doesn't have a socket for you to supply your own like the 6809 does.

Thank you that will be extremely useful to put it mildly - I'll let you know on the RAMs ASAP. I just need to look and see if I have any. I'm pretty comfortable that the RAMs will have been removed as it's a faulty board, not that the lack of RAMs are the fault, but obviously working RAMs are needed anyway...

I've got an A500+ board that is scrap in the shed but I think it's already missing it's CPU and all my other Amiga stuff is SMT. I must have a board with a working 68K somewhere.

Failing that, I guess it's a case of stick a logic analyser on any buffer chip there may or may not be and see if the 68K looks like it's reading instructions.

Hmm, this isn't looking too good. I distinctly remember the last time I looked at this it failed it's self test. Now it does nothing, I get "No POD connected" or whatever the exact wording, there is no clock signal on the board and on power up the fluke usually blows it's main fuse with the pod connected.

I am going to need to look at the schems for this pod and take a trip to Maplin for some more fuses! (Which is a pain as it's a 50 mile round trip - I may do it by post!). Also forgot to look for those RAMs too.

Resolved the issue with it not detecting the POD at all - the voltage protection custom chip was missing (U20 on the I/O board). God knows what's happened to that chip. The last person I sent the POD to reckons they don't have it so it must be here somewhere but I don't remember ever taking it out. Will have to go hunting for that, but for the minute I've nicked the one out of my 8080 pod since I never use that pod.

Which brings me back to pod self test failure with error code 0.

Now the manual reckons the fact self test returns at all means the top (cpu) board has to be working correctly but I don't believe that for 1 second since I can get an error code of 0 if I remove the 68K completely. The 68K pod manual was written in the days of the 9010 and the 9100 supplemental pod manual has updated error codes listed because the 9100 has updated self-test routines.

It reckons error 0 means unable to reset the pod, or drive data and / or address lines. Which basically means all bets are off and it's a fail at the first hurdle. I've pulled and tested everything that I can on the bottom board and oddly a few times self test just completed. So it's beginning to look like either a bad connection somewhere or a marginal fault. As yet (obviously) I can't find it.

Damn it I hate faults like this. Hours and hours of demoralising going round in circles getting officially nowhere fast. And I already feel like chucking it back on the shelf for another 5 years!

Just for giggles I pulled the ROMs and RAM (RAM tested fine). The CRC32's for the ROMS are:

Thanks guys. My ROMs are definitely different, but they look properly structured to me. I can see what looks like header, trailer (or perhaps checksum) and padding at the start and end. So I'm wondering if mine are simply a later revision.

I'll try the ones you've supplied though just in case.

I also dumped the PAL and mine has less in it than the one on Porchy's site (which I didn't know about!). Mine is 2048 bytes, Porchy's is 2194 bytes. Again, provided I've got a suitable GAL I can give it a try...

PS: I understand that people may not want to open up working 68000 pods but if anyone cares to dump the ROMs just in case there are different revisions out there then that would be cool. Be warned though there's heatsinks and all sorts in that POD.

I was wondering if UV had got to my POD while I was converting the garage as I can remember where it was and it was near a window. I doubt it, but again, I can try.

Depending on the programmer used to dump the PAL will depend on how big the file is. Different programmer specific info is prepended.If you (or I can if you want) reverse both Jed files then the equations can be compared.That Eprom dump on my site is from my pod and I can try running g your roms in my pod if you want?

On the PAL, I'm going by the size reported in the JED file, not the size of the JED file itself. So for instance you dump has QF2194 and my dump has QF2048 and sure enough, comparing down through the binary data, everything is the same right up to there end where your's has an additional:

*L02112 00000000111111111111111111111111

*L02144 11111111111111111111111111111111

*L02176 111111111111111111

If you're willing to give my ROMs a shot then that would certainly help me and be awesome! I'd fully appreciate it if you didn't want to though. I'm not sure I'd be all that keen to take a fully working pod apart

Just a thought, were your ROMs labelled up with a part number and all that jazz? Mine are just plain windowed Intel D2732A and don't even have labels over the windows - although the heatsink that is clipped on does completely cover the window.

Ah OK - I think I can assume the PAL is OK then. If you PM me an email address, or email me on martin at guddler dot co dot uk then i'll forward the ROM dumps from mine. That would be hugely useful and we may even discover that there is a later version you could use to upgrade your POD - although who knows what may or may not be new in it, or how we would find out.

I've just been having a nose at your site as well. Don't know why I've never seen that before. In particular there's a Rainbow Islands repair log there that could be really, really useful as the symptoms are identical to mine. Couple that with some of the info on your site and I may try and find it to have another look...

Thanks immensely to Porchy and also ed for emailing me some ROMs over. I spent the day exchanging emails on and off with Porchy which kept me going at this and after trying new ROMs and having another prod about I've come to a somewhat annoying conclusion! Apart from the missing protector chip which is still MIA and I'll likely end up having to try and source one of them, I've arrived at the conclusion that there is nothing wrong with this POD, and in all likelihood never has been.

If there was an emoticon for slapping your forehead I'd be inserting it right here!!!

Bottom line is the test socket on the pod is a bit iffy. I ended up painstakingly beeping out all 64 contacts at both ends of the POD cable, socket and the points in between and found pinouts that individually were all OK but put them all together and there was no connectivity.

If I push really hard on the test plug when it's in the socket (which I don't want to do too often!) then self test passes. So in all likelihood when this pod is plugged into a working board it will work just fine. Hopefully I'll be able to prove that soon enough. I just need to forget about self test and get myself some sockets!!

Oh, and along the way I've found that the donor scrap Amiga 500+ motherboard had a working socketed 68K. Bonus

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